A minor character in Raymond Chandler's 'The Big Sleep' wouldn't let Steinberg go, so she built a novel around the young woman.

Janice Steinberg's latest creation isn't technically her creation at all. Rather, the protagonist in her new novel, "The Tin Horse" (Random House: 352 pp., $26 hardcover), is the fully formed version of a marginal character plucked from Raymond Chandler's "The Big Sleep," a figure Steinberg had been preoccupied with for a while.

An unnamed young woman who appears for a few brief pages in Chapter 5 of Chandler's famous noir — she's in a bookstore, reading a law book, when the detective Philip Marlowe wanders in and asks her about one of the other stores on the street. She is described as a "small dark woman reading a law book at a desk," who had the "fine-drawn face of an intelligent Jewess." They exchange some sassy talk, and that's that. But Steinberg was transfixed.

Over decaf lattes at a café in Boyle Heights, the Eastside neighborhood where "The Tin Horse" takes place, Steinberg says, "I couldn't identify with the tough guys who had their first drink at 10 a.m. or the fast women.... But then there's this nameless character in a three-page scene. This is the one person who might be me. Her repartee with Marlowe is so sharp. I know this woman, and I want to know about her.

"I didn't have a premise or a story," says Steinberg, who has written five mystery novels, the last of which was published in 1998. "I just had a person." What followed was an act of imagination and meticulous research that re-creates a world that Steinberg, 63, had never known.

First came deduction: "She's Jewish," says Steinberg. "She lives in L.A. She was reading a law book. She must have been a lawyer, right? Who else reads law books?" "The Big Sleep" had been published in 1939, but Steinberg moved the meeting between the young woman and Philip Marlowe to 1941.

So Steinberg set about learning everything she could about the imaginary young woman and her times, extrapolating details from the few pages of talk and description Chandler provided. She assumed that though the bookstore Marlowe found the young woman in was in Hollywood, if she were Jewish and working class at that time, she would have lived in Boyle Heights.

"I had no idea Boyle Heights existed," says Steinberg, who lived in Los Angeles in the '70s. (She currently lives in San Diego.) The neighborhood has changed a lot since the early part of the 20th century, when Steinberg's novel is set, but it is still populated by an immigrant population, albeit now a mostly Latino one. As Steinberg walks through the neighborhood, she describes the changes that came when the Interstate Highway plan brought in the 10 Freeway in the 1950s and what it was like before it.

"It was like a utopian experiment that really happened by accident," she says now of the Boyle Heights of the 1920s and '30s, where the Jewish working-class population lived among Japanese and Mexican immigrants. "These were people who couldn't live in other parts of L.A. There was restrictive housing, or they couldn't afford it. What they had in common was that they were working people. The neighborhood accepted them."

Steinberg spent time at the Jewish Historical Society of Southern California listening to audiotapes of testimonials from people raised in Los Angeles in the early part of the 20th century. Some of the stories she heard made it in, but mostly she used them as inspiration for her own stories. "I didn't want to feel like I was stealing ideas," she says.

She accumulated six thick folders full of research on dance (the character's twin was a dancer, and Steinberg herself writes about dance and is certified in Nia, a movement practice), Zionism, food, the economy, worker unions. A historian in Steinberg's writer's group in San Diego pointed her toward Harriet Rochlin, whose book "Pioneer Jews" was so helpful that Steinberg named a character in the book after her (Harriet is also the name of Steinberg's mother).

Steinberg and her husband, a retired computer programmer, took bus tours of Jewish Los Angeles, visiting the school and synagogue Elaine would have attended, including the Breed Street Shul. "More than 1,000 people were going to high holiday services here," she says, standing in front of the now-decrepit synagogue, which has collapsed steps and a fence around it. There is a building annexed to the side of it, which is where Steinberg will have a reading and book-signing Feb. 24. There is a movement to rehabilitate the building for use again, which harks back to its early days. "It's not just Jews who want to rebuild this. The Hispanic population wants it to work again, so it can be a community center."